Self-assembly of heteroleptic [Cu(dipyrrinato)(hfacac)] complexes directed by fluorine-fluorine interactions

Heteroleptic copper(II) complexes were synthesized from three different meso-substituted pyridyl- and quinoline-dipyrrinato ligands (3-pyrdpm, 3-quindpm, and 4-quindpm). Metal complexes were prepared with both acetylacetonate (acac) and hexafluoroacetylactonate (hfacac) ancillary ligands. The complexes undergo a self-complementary self-assembly process upon crystallization to generate a range of solid-state topologies including one-dimensional coordination polymers and discrete hexameric rings. The self-assembly of these molecular aggregates is driven by metal-ligand bonding, but is also modulated by fluorine-fluorine interactions. Perfluorination of the spectator ligand tends to generate more compact structures, which is attributed to aggregation of the perfluoromethyl groups. The results presented here demonstrate that fluorine-fluorine contacts can be used to modulate supramolecular structures in the solid state.